Unit 4 Helping out Grammar 课件 2025-2026学年译林版八年级英语下册

该初中英语课件聚焦八年级下册Unit 4情态动词表推测语法点，通过对比事实陈述与推测句（如“蜡笔携带病毒”vs“蜡笔可能携带病毒”）导入，搭建从已知到新知的学习支架，结合推测定义、语气排序表及“情态动词+动词原形/ be doing”结构公式，帮助学生梳理知识脉络。 其亮点在于通过对比分析（思维品质）辨析must/may/might等语气强弱，任务型活动（快问快答、对话填空）提升语言运用能力（语言能力），口诀“肯定must最强，否定can’t记牢”及表格总结（学习能力）强化记忆。实例有进行时结构“must be sleeping”、易错点“mustn’t表禁止非推测”，助力学生准确运用推测，教师可高效开展语法教学。

八年级英语下册 Unit 4 Helping out grammar rules Grammar 情态动词表推测 【学习目标】 1、掌握 must / can / may / might / could / can’t 表推测 的用法 2、能根据语气强弱正确选择情态动词 3、掌握现在推测 / 进行推测两种结构 4、能在写作与口语中正确运用 5、辨析常见易错点 P55 Read the sentences ,compare and summaries the grammar rules (a) well, crayons carry viruses and spread disease. 嗯，蜡笔携带病毒并传播疾病。（事实陈述） well, crayons may carry viruses and spread disease. 嗯，蜡笔可能携带病毒并传播疾病。（推测，可能性） (b) It is boring to wait for X-rays and treatments. 等待 X 光检查和治疗很无聊。(陈述事实） It can be boring to wait for X-rays and treatments. 等待 X 光检查和治疗可能会很无聊。（推测） (c) There is something for me to do. 有些事情是我可以做的。（陈述事实） There must be something for me to do. 一定有什么事情是我可以做的。（推测、可能性） 什么是推测？ 对事情不确定的判断 表达可能性大小 结构：情态动词 + 动词原形 语气强度排序 must（一定）> may（可能）> might /could（或许） can’t（不可能）= must 的否定 can（理论上可能） 情态动词 推测语气强度 含义 关键特点 例句 must 最高（≈95%） 一定、肯定 只用于肯定句，有明确事实依据 The light is on. He must be at home. （灯亮着，他一定在家） can’t 否定最高（≈95%） 不可能 对应 must 的否定，不用 mustn’t 表推测 He can’t be at home. The light is off. （灯灭了，他不可能在家） may 中等（≈30%-50%） 可能、也许 不确定的推测，可肯可否 It may rain this afternoon. （下午可能下雨） might 更低（≈20%-40%） 或许、大概 比 may 更不确定，语气更弱 She might not come to the party. （她或许不来派对了） can 弱（理论上的可能） 有时会、可能 多用于否定 / 疑问句，肯定句少 It can be cold in the mountains. （山里有时候会很冷） could 弱（委婉的可能） 可能、也许 比 can 委婉，也可表过去的可能 He could be at the library. （他可能在图书馆） 快问快答 1. 灯亮着 → He ______ be at home. 2. 她在北京 → That ______ be Lucy. 3. 我不确定 → It ______________ rain. 4.他工作一整天 → You ______ be tired. msut can't may/might must 1） You _______ be thirsty now after the long run. Here is a bottle of water for you. 2)You didn't bring an unbrella? Take mine. It ______ rain later. 3) Here is my notebook. You ____________ return it after the exam. must may can/may must may can can't can 笔记: 精+助+副+实：指的是“情态动词 + 助动词 + 副词 + 实义动词” 的顺序规则 1. 推测语气强弱排序 must > may > might / could （can/can’t 单独记，表理论可能或否定推测） 2. 进行时结构 统一公式：情态动词 + be + doing He must be sleeping.（他一定正在睡觉） She may be reading.（她可能正在看书） They could be playing basketball.（他们可能在打篮球） 3. 易错辨析 ❌ 错误：He mustn’t be at home.（表推测时，mustn’t 是 “禁止”，不是 “不可能”） ✅ 正确：He can’t be at home.（他不可能在家） ❌ 错误：I might swim when I was 5.（表过去能力不用 might） ✅ 正确：I could swim when I was 5.（我 5 岁时就会游泳了） 一、选词填空：must /may/might /can't 1.The light is on. He ___________ be at home. 2.He is only five. He ___________ go to school. 3.I’m not sure. It ____________ rain tomorrow. 4.That ___________ be Lucy. She is in Beijing now. 5.The book looks like Tom’s. It ____________ be his. 6.It __________ be true. I don’t believe it. 7.She __________ know the answer, but I’m not sure. You ________ be tired. You worked all day. must can't may / might can't must /may can't may / might must 二、单项选择（表推测） 1. — Who is knocking at the door? — It ______ be Mary. She is coming today. A. can't B. must C. may not 2. The man ______ be our teacher. Our teacher is much taller. A. must B. may C. can't 3. It ______ be sunny this afternoon. We plan to go shopping. A. might B. can't C. mustn't 4. You ______ be hungry. You had nothing for breakfast. A. can B. must C. may not 三、句子改写 同义转换 Maybe he is in the library.（用 might） He ______ ______ in the library. I’m sure it’s his bike.（用 must） It ______ ______ his bike. It’s impossible that she is ill.（用 can't） She ______ ______ ill. might be must be can't be … may find it a challenge to…… 可能会发现做…… 是一项挑战 … need a helping hand. … 需要搭把手 / 需要帮助 Perhaps I can / could… 也许我可以…… … help… get through… … 帮助…… 渡过 / 完成…… There must be something for me to do, such as… 一定有我能做的事，比如…… 1. … may find it a challenge to… We may find it a challenge to learn English well. 我们可能会发现学好英语是一项挑战。 2. … need a helping hand. I need a helping hand with my homework. 我写作业需要搭把手。 3. Perhaps I can / could… Perhaps I can help you clean the classroom. 也许我可以帮你打扫教室。 4. … help… get through… My friend helps me get through hard days. 我的朋友帮我渡过艰难的日子。 5. There must be something for me to do, such as… There must be something for me to do, such as cleaning the window. 一定有我能做的事，比如擦窗户。 A Helping Hand Sometimes, we may find it a challenge to keep up with schoolwork. When we are in trouble, we all need a helping hand. Perhaps I can give a helping hand. I can help my classmates get through difficult homework or hard days. There must be something for me to do, such as sharing my notes or practicing with them after class. A helping hand is not just about doing things for others. It is about being there when someone needs you. Small kindness can make a big difference. 有时候，我们可能会觉得跟上课业进度是一件很有挑战的事。当我们遇到困难时，都需要有人伸出援手。 也许我可以伸出援手。我可以帮同学攻克难懂的作业，或是陪他们度过难熬的日子。 一定有我能做的事，比如分享我的笔记，或是课后和他们一起练习。 伸出援手不只是为别人做事，更是在别人需要的时候陪在他们身边。小小的善意，也能带来大大的改变。 Summary 课堂小结 肯定推测 must 最强， may 中等，might 弱更长。 否定推测 can’t 上， mustn’t 禁止不能忘。 进行推测 be doing， 现在推测原形用。 Homework 作业 1. 背诵用法表格 + 口诀 2. 完成课本 P55 练习 3. 用今天句型写6 个句子 4. 熟读范文，尝试仿写一段 $